The field of invention relates to pneumatic tires. The invention particularly relates to run flat tire supports for pneumatic tires.
In past years, the automotive industry has provided spare tires for replacement of punctured or blown out tires while traveling. However, efforts have been made to eliminate the need for the spare tire by providing improved designs for tires. Specifically, efforts have been made to provide a stable and economical tire that can run with little or no pressure when, for example, the tire is flat. The term for the efforts has become known as xe2x80x9crun flat tirexe2x80x9d (RFT) technology. The RFT concept allows an operator to continue driving or rolling for an extended period of time without stopping to replace the tire or seeking emergency assistance. A tire can be repaired at a later, more convenient time.
One embodiment of an RFT wheel assembly includes a rim, a tire mounted on the rim, and a support sandwiched between an inner surface of the tire and an outer peripheral surface of a rim. The support allows the tire to deflect a limited amount so that the tire does not separate from the rim along each edge of the tire. A synthetic material, such as a polymer, is typically used for the support.
The process of producing an RFT support typically involves some type of molding. A mold for the support can include a narrow channel of about three millimeters (mm) in width that is formed about an inner or outer periphery of the mold. The polymer support can be reinforced to help maintain its structural integrity during adverse conditions by providing a reinforcement in the molding process. The reinforcement is placed in the channel prior to molding and the polymer typically flows therethrough to encapsulate the reinforcement into the molded RFT support.
RFT supports can vary by manufacturer, size, style, and other attributes. Shipping, installation, repair, and other post-manufacturing uses need clear identification of the various RFT supports. For example, different RFT supports can be unintentionally and perhaps dangerously installed on improper rims and/or tire combinations.
Therefore, there remains a need for an RFT support that includes some visual indicator of one or more of the attributes of the RFT support to avoid confusion with other RFT supports.
The present invention provides a unitary run flat tire (RFT) support that includes a visual colored indicator. The colored indicator can be formed reinforcement that is formed into a relatively rigid shape. Generally, the unitary RFT support reinforcement can be formed from multiple layers that are coupled together, such as with an adhesive, to form one effective layer. The one effective layer can include layers of cloth or, advantageously, layers of filaments wound into a reinforcement. The reinforcement is insertable into a mold for an RFT support and can maintain the needed structural rigidity for such insertion.
Further, the invention provides an RFT support that is molded and includes the RFT reinforcement. The invention also provides a wheel assembly including a tire, a rim, and an RFT support between the rim and the tire, where the support includes the RFT reinforcement. The RFT support can have a colored indicator formed or subsequently applied thereto to indicate one or more attributes of the support.
The present invention provides a run flat tire (RFT) support, comprising a molded portion having an outer circumference and an inner circumference and adapted to mount to a wheel rim to support a deflated tire when the tire is rolling on a surface, the molded portion further comprising a colored indicator that indicates at least one attribute of the RFT support; and at least one RFT reinforcement molded into the molded portion.
An RFT support is provided, comprising a molded portion having an outer circumference and an inner circumference and adapted to mount to a wheel rim to support a deflated tire when the tire is rolling on a surface, the molded portion having a colored indicator that indicates at least one attribute of the RFT support.
A method of manufacturing an RFT support is also provided, comprising flowing a moldable material into an RFT support mold to form the RFT support; and visually identifying at least one attribute of the RFT support by adding a preselected colorant to at least a portion of the RFT support.
A method of installing an RFT support on a wheel rim is also provided, comprising selecting a wheel rim; and selecting an RFT support suitable to the wheel rim based on a colored indicator formed on the RFT support, the colored indicator indicating at least one attribute of the RFT support.